Bird feeder



FIG. 1 is an isometric view of a bird feeder incorporating my new design;

FIG. 2 is an enlarged elevational view of any of the four sides thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof.

The broken lines shown in all figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a bird feeder, as shown and described. 